1. FIELD OF THE INVENTION
This invention relates in general to the construction of coke ovens and in particular to a new and useful apparatus for charging coal into the individual filling openings of each coke oven of a coke oven battery.
2. DESCRIPTION OF THE PRIOR ART
A coke oven charging car is known in which each hopper which is carried on the car is associated with a lowerable and horizontally movable connecting piece which is engageable into the filling frame and into which the outlet connection of the hopper projects. In this construction closure elements are provided which close the feed passage in response to a signal of the filling level meter in the hopper as soon as the coal has been completely discharged except for a residual volume which seals the valve or shutter which operates to close the opening. Such a construction includes in addition to a shutter valve a rotary slide valve which serves as a closure element. Such hoppers are designed with lower ends forming a funnel for transferring the coal from the hopper into the oven. The small residual volume which remains in the hopper seals the space over the shutter valve which is made smaller than the output opening of the hopper. Such a coke oven charging car has proved quite satisfactory in practice and about thirty of these cars are in service. The hoppers of such devices include funnel shaped connecting pieces which are engageable into the filling openings of the coke oven roof and this makes it necessary to locate sensitive mechanism or devices such as hydraulic, pneumatic or electrical or electromagnetical lifting devices and linkages closely adjacent the connecting piece and beneath the service platform in the immediate vicinity of the filling opening of the oven and sometimes particularly during disturbances flames flare up which may damage the parts or even set them on fire. This is hazardous especially with oil hydraulic motors.
In operation it may also occur that the filled charging car is displaced into a position above the oven chamber to be fed and because of a disturbance, the coal is discharged into the oven chamber either completely or only partially. Then the connecting pieces which have already been lowered for the coal discharge are to be retracted and the charging car is to be displaced away from the oven chamber. Consequently at the final discharge of the coal, difficulties may arise since during the preceding retraction of the connecting piece the loose fines received therein have been jolted and compressed. In the connecting piece and therefore in the outlet connecting the hopper the compressed coal obstructs the free discharge and flow of the main volume of the coal. So called "bridges" of compressed coal also tend to form. The formed structures of compressed coal must be cleared or removed by manual work. Also upon formation of a bridge in the hopper, the transfer funnel may become completely emptied and because of the absence of a protective coal cushion, the charging might be exposed to flames flaring up from the oven chamber.